Night diving or low viz diving

[Octopusprime]

I recently did a deep dive where vis went from 40' to 5' as we descended to 40' deep. We were descending on a line and all I could see of my buddy was his arm. We both instinctively stopped and got our lights out of our pockets and hung them on our BCD so we could see each other.

We have talked about doing night dive speciality and figure it will be similar to the vis of that deep dive. I have been looking at lights glow sticks and the like and was wondering where do you put the glow stick (or led equivalent) and how many do you need? By SMB has a sleeve for one. We both already have 2 lights one about 1000 lum and a 400-600 lum light.

I was thinking of getting 2 of the led sticks one for tank valve and one for front of BCD. I try to be green so I don't want to go threw 12 glow sticks either...

any suggestions.

 

[Peter Guy]

"Any suggestions?". Why, yes!

We dive in dark, murky water pretty much all the time and use strong lights (21 watt HIDs) on every dive. The benefit of these (and similar) lights is that they not only allow you to see things clearly, but they allow you to "extend your body" by 10 feet or more so that your buddy can easily "see" you whether directly beside you, slightly above/behind/below and you can see your buddy easily. In addition, as long as the light is being calmly "swept" back and forth, we know there is nothing wrong so we are communicating with each other all the time -- what is called passive communication.

With strong, FOCUSED lights of this sort, there is no need for glow sticks or other such devices. (But, a group of us were on a boat that required glow sticks for a night dive and one of the divers made the snide comment -- "I can now be seen" as if having our HID lights didn't provide enough information to each other! And no, you couldn't actually see the glow sticks over the HID lights.)

Diving with strong, focused lights does require "light discipline" -- that is, you need to be able to keep your light stable which means no flapping of hands, no dropping the light and having it spin "disco style" and generally means having a method to mount the light on the back of your hand which then frees your fingers to be useful.

Lights are great tools and need to be thought of as such.

 

[Octopusprime]

On the deep dive I had my primary light mounted to the gopro for video and 2nd light was hanging off BCD .... Our plan was to descend to bottom then circle the bottom of hole. I found a pipe I followed maybe 5-6' and I turned around and I could not see my buddy because his back was to me and I could not see his light. I followed pipe back to line and found buddy was only 20-30 sec but I was thinking a light on the back or tank would be a good idea.

 

[Dhboner]

The idea of a good primary light (and back-up lights) is that you can not only see your team at all times but you can use the light for communication. Glow sticks have no purpose on a dive. If you cannot see without lights then you either use proper lights or scrub the dive and stick to daylight.

 

[tbone1004]

Piranha sells glo-toobs that are good for night diving if the ops want color coding. You can tie them onto the tank neck and it works fine, but other than ID'ing your buddy if it's color coded, or for the dive ops to be able to count from the surface, they're pretty useless. $20 for the color of your choice and uses AAA batteries.
Glo-Toobs, LED Light Beacons & Sticks

Night diving and low viz diving are completely different environments. In a cave, it is truly pitch black with lights out, but since the visibility is often well over 80ft, you are limited by the penetration of the light not the water. Most night diving is done in similarly clear water, and with that you don't need a great deal of light to be able to signal buddies, but you need the right lights to do it for the environment you're in. If you were truly in 5' of visibility no light on the market is going to make it easier to see your buddy and in that low vis it is recommended that you go to touch contact or at least close enough where you can reach out and touch your buddy at all times.

 

[Octopusprime]

Piranha sells glo-toobs that are good for night diving if the ops want color coding. You can tie them onto the tank neck and it works fine, but other than ID'ing your buddy if it's color coded, or for the dive ops to be able to count from the surface, they're pretty useless. $20 for the color of your choice and uses AAA batteries.
Glo-Toobs, LED Light Beacons & Sticks

Night diving and low viz diving are completely different environments. In a cave, it is truly pitch black with lights out, but since the visibility is often well over 80ft, you are limited by the penetration of the light not the water. Most night diving is done in similarly clear water, and with that you don't need a great deal of light to be able to signal buddies, but you need the right lights to do it for the environment you're in. If you were truly in 5' of visibility no light on the market is going to make it easier to see your buddy and in that low vis it is recommended that you go to touch contact or at least close enough where you can reach out and touch your buddy at all times.

On our dive it was really odd it was like we went through a thermocline of silt. My guess is there was sediment that was sitting on top of the thermocline. And it went from sunny and good vis to lights out... Vis was better at bottom but lights out. We stayed close but when his light was blocked by his body I just thought a tank light would be helpfull.

 

[tbone1004]

you need to work on better buddy positioning for situations like that. If the vis was good just dark at the bottom that's a different thing. You say you're carrying lights, what lights are you carrying? There is a big difference in good backup size lights and not so good backup size lights.

 

[Octopusprime]

I have a Princeton shockwave II and Princeton Tec league the league was mounted to my gopro camera and I was using for nav too since I did not have a free hand.

Still no one has answered the question about body position? Even if you have the beast light for situation if light is obstructed by diver do you recommend a tank light?

 

[tbone1004]

I don't use one, nor do any of my buddies in any environment unless required by the dive op. No offense to the purchases that you have made, but the better option would be to get a light that is actually designed for that type of work and it will solve a lot of your problems.

https://www.divegearexpress.com/lights/backuplt.shtml
Spend $60 and grab one of the DGX600's with a soft goodman handle. You'll have a light that is 4x brighter than the Shockwave II, tighter spot so it throws farther and better through low vis, and with the goodman handle you don't have to hold onto anything.

 

[TSandM]

If it's just dark, you can see a strong light pretty well, even if it is aimed away from you -- it will illuminate enough area to be seen. If the viz is very poor (whether you have lights or not!) then team formation becomes quite important. At that point, you stay close together, preferably shoulder-to-shoulder, but if diving along a wall or hull, in close single file. It comes a matter that requires some attention, to keep the light aimed not only where you want to look, but also where it will be visible to your buddy. In such conditions, one simply doesn't turn one's back on the team.